Many medical device applications require advancement of device in a reduced profile to a remote site within the body, where on reaching a target site, the device assumes or is deployed into a relatively larger profile. Applications in the cerebral vasculature are one such example of medical procedures where a catheter advances from a remote part of the body (typically a leg) through the vasculature and into the cerebral region of the vasculature to deploy a device. Accordingly, the deployed devices must be capable of achieving a larger profile while being able to fit within a small catheter or microcatheter. In addition, the degree to which a physician is limited in accessing remote regions of the cerebral vasculature is directly related to the limited ability of the device to constrain into a reduced profile for delivery.
Treatment of ischemic stroke is one such area where a need remains to deliver a device in a reduced profile and deploy the device to ultimately remove a blockage in an artery leading to the brain. Left untreated, the blockage causes a lack of supply of oxygen and nutrients to the brain tissue. The brain relies on its arteries to supply oxygenated blood from the heart and lungs. The blood returning from the brain carries carbon dioxide and cellular waste. Blockages that interfere with this supply eventually cause the brain tissue to stop functioning. If the disruption in supply occurs for a sufficient amount of time, the continued lack of nutrients and oxygen causes irreversible cell death (infarction). Accordingly, immediate medical treatment of an ischemic stroke is critical for the recovery of a patient.
Naturally, areas outside of ischemic stroke applications can also benefit from devices that can assume a profile for ultimate delivery to remote regions of the body.
Regardless of the area where the device is to be used, when fabricating such a device the joints between adjacent shapes or sections of the device often impede the ability of the device to assume a sufficiently reduced profile or interfere with the geometry/stiffness of the device causing problems when navigating the device through the body. Also, joints lead to potential failure locations, and may lead to fractured and embolized components within the body. Such joints may include welded, glued, or otherwise separately joined pieces into one or more points of connection.
Accordingly, a need remains for devices that can assume deployed configurations and are fabricated to eliminate or reduce the number of joints and/or connection points in the device. Doing so allows the device to have a compact and smooth configuration making it easier for delivery through a microcatheter, and leads to a safer device less prone to breaking or embolizing.